A confocal microscopic evaluation of the hybrid layer and resin tag formation of a total etch technique in comparison with self etching primers with three different pH

Abstract

<b>Aim:</b> A Confocal Microscopic Evaluation of the hybrid layer and resin tag formation -of a total etch technique in comparison with self etching primers with three different ph.<br><b>Materials and Methods:</b> 20 non carious human premolars stored in normal saline were used for the study. Occlusal surfaces of all the teeth were ground using slow speed diamond disc with copious <i> water </i> supply, <i> so </i> as to expose a flat surface of dentin with an approximate residual dentin thickness of 1.5-2mm. The teeth were then randomly divided into 4 groups of 5 specimens each. Group 1: (Blot dry)­<i> Prime and Bond NT (Dentsply), </i> Group 2; Strong self etch adhesives usually have a ph of 1 or below {<i> Adper Prompt L- Pop (3M ESPP)}, Group 3; </i> Intermediary self etch adhesives have a ph of about 1.5 {<i> AdheSE (Vvadent)}, </i> Group 4; Mild self etch systems have a ph of about <i> 2- {Cleatfil SE bond plus primer (knraray)}. </i> Bonding agents mixed with Rodhamine B dye was applied according to the manufacture's instructions and cured using a light curing unit. All the bonded surfaces were restored with 2mm of resin composite Z 350 (3M) and cured for 40 seconds, to protect the bonding layer. All the specimens were stored in normal saline. After 24 hrs of storage the teeth were longitudinally sectioned using a slow speed diamond disc under copious water supply. The sectioned surface was polished' with a' 600 grit silicon carbide paper. The dentin/adhesive interfacial region was examined using a Confocal Laser Scanning Microscope (CLSM). Statistical analysis was done to compare the values among the groups using Kruskal-Wallis One way ANOVA appropriately by testing the means.<br><b>Results:</b> Statistical analysis demonstrated that Mean length of resin tag formation and thickness of hybrid layer formation in Group I was maximum followed by Group IV; Group II and Group III respectively.<br><b> Conclusion: </b> Within the parameters of this study the Prime and Bond NT (Group 1) performed better than all the three self etching primers in terms of resin tag formation and hybrid layer thickness.